This invention relates to a laminator for laminating structural components, in particular solar module cells or laminated glass panes by combining pressing force and heat, wherein said laminator comprises at least one laminating chamber for receiving one or several structural components which is provided with a support for said structural components, a heating unit and with a flexible compression membrane which is sealingly stretched in the chamber above the structural element support and is movable with respect thereto, separating a lower part of the chamber from a top part thereof, thereby enabling each part to be void of air and aerated.
A laminator of the initially mentioned type is known from WO 94/29106 A1. The compression membrane which serves to produce the pressing force acting upon the structural component during a laminating process is subject to mechanical, thermal and chemical loads during the operation of the laminator. The mechanical loads result from the movements of the compression membrane due to different pressure conditions in the two parts of the chamber on both sides of the compression membrane as well as by pressing the compression membrane to the structural component to be laminated in each case. Thermal loads result due to the heat applied during the laminating process to which the compression membrane is also exposed. The chemical load of the compression membrane results from gases which are released during the laminating process from the structural component to be laminated. Over time, these mechanical, thermal and chemical influences on the compression membrane result in wear which finally results in leakiness of the compression membrane, for example due to rupture. Due to leaky areas of the compression membrane, air can pass during the laminating process in an uncontrolled and undesirable manner from the top part of the chamber into the lower part of the chamber void of air which results in errors or defects on the laminated structural component and thus in the production of rejects. Since with the known laminator, leakiness of the compression membrane is only to be detected in subsequent quality control of the laminated structural components, it is possible that, for a certain time, work is continued with a leaky membrane so that reject products will be produced with the laminator to a greater extent. This is uneconomical and therefore undesirable.
To remedy this disadvantage, it is standard operating practice to prophylactically replace the compression membrane in a laminator after a certain number of laminating processes, irrespective of whether damages on the compression membrane already occurred or not. This will, in fact, prevent the production of rejects; however, frequently, a still intact compression membrane will be replaced so that relatively high costs for spare membranes will be incurred which is also detrimental for the efficiency of operation of the laminator.
From DE 199 20 577 C1, a membrane press is known for the coating of workpieces with a thin coating material, with a lower pressing table, an upper pressing table, an elastic membrane lowerable onto a workpiece covered with the coating material and to be coated therewith, the membrane forming a pressure-proof chamber with a pressing table, and with channels for the inlet and outlet of a fluid admitted to the membrane, and with a press control. It is provided that the press comprises two supply tanks for two fluids with different temperature adjustment, provided with working valves which can be controlled to be opened and closed by the press control, and that the membrane press comprises a conveying device for the fluids. In one embodiment of this membrane press, below a first membrane, a second elastic membrane is provided which forms, via a frame with the first membrane, a second pressure-proof chamber into which a working fluid can be pressed through inlets and outlets depending on the individual process steps. With this membrane press as well, any leakiness in one of the membranes results in an impairment of the function of the membrane press and thus the production of rejects or a standstill of the press. Here again, reliable operation can only be ensured through a regular prophylactic replacement of the membranes which is complex and expensive.